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How long should this nap be?
Tell it when you’re lying down. It adds the minutes it takes you to drop off and gives you the alarm time for a short nap, a power nap and a full sleep cycle, with a note if it’s getting late to nap at all.
10 minutes asleep
A reset when you can barely keep your eyes open and have something to do straight after.
20 minutes asleep
Short enough that most people wake before deep sleep, so there’s little grogginess.
About 90 minutes
Roughly one full sleep cycle. For days when you’re badly short on sleep and have the time.
If you’re napping because last night ran late
We make Sleepward, an iPhone app for people who stay up because the evening is the only time that feels like theirs. It’s a four-minute evening reset: empty your head, pick tomorrow’s three things, have an hour that’s actually yours, then wind down.
- White, pink and brown noise with a fade-out sleep timer, free.
- It never scores your sleep and never breaks a streak.
- No account, no ads, no tracking. Pro is optional.
Why 20 minutes or 90, and not 45
Sleep moves through stages, and the deeper ones arrive after roughly the first half hour. Wake from deep sleep and you get the heavy, confused feeling called sleep inertia. A nap of about 20 minutes usually ends before that point. One of about 90 minutes usually ends after you’ve come back up through a full cycle. In between is where naps tend to feel worse than no nap. Cycle length varies from person to person and night to night, so treat 90 as an average, not a setting.
When it’s too late
Mayo Clinic’s guidance for adults calls a 20- to 30-minute nap ideal, advises against regularly napping for longer than 30 minutes, and suggests the early afternoon, because napping after 3 p.m. can make it harder to sleep at night. The power nap card above (20 minutes asleep, plus the time it takes you to drop off) fits inside that; keep the 90-minute nap for the occasional day when you’re badly short on sleep. The note above uses that 3 p.m. line, or your own bedtime if you enter one: it flags any nap that ends less than six hours before bed as a rule of thumb.
Source: Mayo Clinic, Napping: Do’s and don’ts for healthy adults. The six-hour bedtime buffer is our rule of thumb, not Mayo Clinic’s. This page is general information, not medical advice. If you need to nap most days despite enough time in bed, that’s worth mentioning to a doctor.
Making a short nap work
- Set the alarm before you lie down, and put the phone out of reach so you have to get up.
- Dark and cool gets you asleep sooner, which is most of a 20-minute nap.
- Didn’t fall asleep? Lying still with your eyes shut still counts as rest. Get up at the alarm anyway.
- Give yourself five minutes after waking before driving or anything that needs sharp attention.
Planning tonight instead? The sleep cycle bedtime calculator works backwards from your wake-up time.
Questions people ask
How long should a power nap be?
About 20 minutes of sleep, which with the time it takes to drop off comes to the 20 to 30 minutes Mayo Clinic calls ideal. That is short enough that most people wake before reaching deep sleep, which is what causes grogginess. Add the time it takes you to fall asleep when you set the alarm.
Is a 90-minute nap good?
Occasionally, when you are seriously short on sleep, because it is roughly one full sleep cycle. Mayo Clinic advises against regularly napping for longer than 30 minutes, and it is long enough to affect that night’s sleep if taken late in the day.
What time is too late to nap?
Mayo Clinic suggests the early afternoon and notes that napping after about 3 p.m. can interfere with night-time sleep. People who go to bed late, such as shift workers, can count back from their own bedtime instead.
Why do I feel worse after a nap?
Usually because the alarm caught you in deep sleep, which tends to happen with naps of around 30 to 60 minutes. Try a shorter one.
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